The present invention relates to a xenon inhalation apparatus capable of functionally and safely conducting a cycle beginning from the administration of xenon and terminating in the recovery of the xenon relative to a patient particularly subjected to measurement of cerebral blood flow rate or inspection of lung function.
A prior art xenon inhalation apparatus has adopted a flexible bag having a mixed gas of xenon and oxygen stored therein, management of the mixed gas on the basis of gas concentration only, a reserve bag and a lot of one-way valves as disclosed in U.S. Pat. No. 4,622,976.
In the prior art xenon inhalation apparatus, since a mixed gas of xenon and oxygen is stored in the flexible bag and managed on the basis of gas concentration only, there is a fair possibility of consuming expensive xenon in an amount more than is necessary and preparing a mixed gas in an amount more than is necessary and, in addition, precision in measurement is not so good. Further, since there are used a reserve bag, lots of one-way valves and an indoor air respiration peep valve, respiration resistance becomes large. Furthermore, since a high-pressure gas cylinder is used as a xenon supply source, the prior xenon inhalation apparatus is subjected to restrictions under the High-Pressure Gas Control Act, such as requirements of registering use of a high-pressure gas container and the name of a person responsible for handling high-pressure gas at the competent office, and handling of the high-pressure gas container must rely on the responsible person or must be conducted by those skilled in the art under the supervision of the responsible person.